Wei Y, Mizzen C A, Cook R G, Gorovsky M A, Allis C D
Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Proc Natl Acad Sci U S A. 1998 Jun 23;95(13):7480-4. doi: 10.1073/pnas.95.13.7480.
H3 phosphorylation has been correlated with mitosis temporally in mammalian cells and spatially in ciliated protozoa. In logarithmically growing Tetrahymena thermophila cells, for example, H3 phosphorylation can be detected in germline micronuclei that divide mitotically but not in somatic macronuclei that divide amitotically. Here, we demonstrate that micronuclear H3 phosphorylation occurs at a single site (Ser-10) in the amino-terminal domain of histone H3, the same site phosphorylated during mitosis in mammalian cells. Using an antibody specific for Ser-10 phosphorylated H3, we show that, in Tetrahymena, this modification is correlated with mitotic and meiotic divisions of micronuclei in a fashion that closely coincides with chromosome condensation. Our data suggest that H3 phosphorylation at Ser-10 is a highly conserved event among eukaryotes and is likely involved in both mitotic and meiotic chromosome condensation.
在哺乳动物细胞中,H3磷酸化在时间上与有丝分裂相关,在纤毛原生动物中与空间相关。例如,在对数生长期的嗜热四膜虫细胞中,可在进行有丝分裂的生殖系微核中检测到H3磷酸化,而在进行无丝分裂的体细胞大核中则检测不到。在此,我们证明微核H3磷酸化发生在组蛋白H3氨基末端结构域的单个位点(Ser-10),这与哺乳动物细胞有丝分裂期间磷酸化的位点相同。使用针对Ser-10磷酸化H3的特异性抗体,我们表明,在四膜虫中,这种修饰与微核的有丝分裂和减数分裂相关,其方式与染色体浓缩密切一致。我们的数据表明,Ser-10处的H3磷酸化在真核生物中是一个高度保守的事件,可能参与有丝分裂和减数分裂的染色体浓缩。